State profile · Above national median SD

Iowa bridge safety

Condition ratings, load ratings, and structural-deficiency data for every public highway bridge in Iowa — drawn straight from the FHWA National Bridge Inventory.

20,753
Public bridges
36.5%
Good condition
20.0%
Poor condition
20.0%
Structurally deficient

Total Bridges

20,753

Public highway bridges in Iowa

Good Condition

36.5%

7,582 bridges rated 7-9

-13.5pp vs 50% benchmark

Poor Condition

20.0%

4,153 bridges rated 0-4

Structurally Deficient

20.0%

4,153 bridges flagged for repair priority

13.0pp vs national avg 7.0%

Iowa vs national bridge condition

Iowa — Good condition share 36.5%
National avg

Share of bridges rated 7-9 on the FHWA 0-9 scale (deck, superstructure, substructure all good).

Iowa — Structurally deficient share 66.7%
National avg

Lower is better. Bar maxes at 30% (worst-state ceiling). National average sits at 7.0%.

Condition Distribution

Bridge inventory deck-condition mix — Iowa (FHWA NBI)

Iowa36.534476943092564%38.39444899532597%20.011564593070883%20.011564593070883%GoodFairPoorStructurally Deficient
Bridge inventory deck-condition mix — Iowa (FHWA NBI)

Counties (99)

Adair 208 Adams 147 Allamakee 170 Appanoose 159 Audubon 161 Benton 327 Black Hawk 411 Boone 119 Bremer 220 Buchanan 281 Buena Vista 140 Butler 261 Calhoun 171 Carroll 223 Cass 237 Cedar 265 Cerro Gordo 210 Cherokee 223 Chickasaw 268 Clarke 150 Clay 138 Clayton 214 Clinton 325 Crawford 242 Dallas 154 Davis 156 Decatur 178 Delaware 254 Des Moines 156 Dickinson 73 Dubuque 304 Emmet 70 Fayette 288 Floyd 195 Franklin 214 Fremont 133 Greene 150 Grundy 270 Guthrie 236 Hamilton 134 Hancock 128 Hardin 211 Harrison 162 Henry 144 Howard 193 Humboldt 70 Ida 164 Iowa 189 Jackson 209 Jasper 321 Jefferson 142 Johnson 317 Jones 215 Keokuk 152 Kossuth 256 Lee 185 Linn 428 Louisa 134 Lucas 186 Lyon 241 Madison 221 Mahaska 219 Marion 204 Marshall 283 Mills 170 Mitchell 160 Monona 125 Monroe 126 Montgomery 184 Muscatine 127 O'Brien 229 Osceola 176 Page 185 Palo Alto 114 Plymouth 407 Pocahontas 186 Polk 415 Pottawattamie 469 Poweshiek 221 Ringgold 206 Sac 188 Scott 212 Shelby 194 Sioux 429 Story 262 Tama 307 Taylor 220 Union 153 Van Buren 142 Wapello 160 Warren 231 Washington 203 Wayne 163 Webster 179 Winnebago 48 Winneshiek 317 Woodbury 379 Worth 89 Wright 168

Iowa vs nearby ranks

Adjacent states on the structurally deficient leaderboard (lower share = better)

States are ranked by share of bridges flagged structurally deficient — the FHWA classification for any span where deck, superstructure, or substructure carries a condition rating of 4 or below. Lower percentages indicate stronger maintenance funding and inspection follow-through. States here sit immediately above and below Iowa on the same metric.

54

West Virginia

16.02% top marginal rate
Structure
Progressive
Burden @ $100K
$7,679

46

South Dakota

16.24% top marginal rate
Structure
Progressive
Burden @ $100K
$5,905
Selected

19

Iowa

20.01% top marginal rate
Structure
Progressive
Burden @ $100K
$20,753

78

Virgin Islands

29.17% top marginal rate
Structure
Progressive
Burden @ $100K
$24

Bridges Needing Most Attention in Iowa

Six lowest-condition bridges in Iowa, ranked by composite NBI rating. Each is inspected at least every 24 months.

270TH STREET

Structurally Deficient

Over: ROSE BRANCH

071343401, Adams, IA

Built 1976 Load: 2.7 t ADT: 79

LOCAL

Poor

Over: CREEK

078342601, Audubon, IA

Built 1935 Load: 2.7 t ADT: 21

KLINE RD

Structurally Deficient

Over: MUD CREEK

87-12-15-02-10, Black Hawk, IA

Built 1948 Load: 2.7 t ADT: 11

LOCAL - 700TH

Structurally Deficient

Over: TRIB TROUBLESOME CREEK

077351402, Cass, IA

Built 1983 Load: 2.7 t ADT: 11

LOCAL - DAYTONA

Structurally Deficient

Over: BUCK CREEK

077361903, Cass, IA

Built 1980 Load: 2.7 t ADT: 35

100TH ST.

Structurally Deficient

Over: UNION CREEK

083E20101, Clinton, IA

Built 1900 Load: 2.7 t ADT: 78

All Bridges in Iowa

LOCAL

Good

Over: BRANCH WOLF CREEK

086141101, Tama, IA

Built 2007 Load: 48.2 t ADT: 39

FM

Good

Over: WOLF CREEK

086161903, Tama, IA

Built 2003 Load: 48.2 t ADT: 34

FM

Good

Over: BUTCHER CREEK

077232605, Warren, IA

Built 2004 Load: 48.2 t ADT: 45

FM

Good

Over: NINE MILE CREEK

070223202, Wayne, IA

Built 2003 Load: 48.2 t ADT: 35

LOCAL

Good

Over: VILLAGE CREEK

098041410, Allamakee, IA

Built 2005 Load: 48.3 t ADT: 33

N16 610TH ST

Good

Over: BEAR BRANCH OF TURKEY CR

075360806, Cass, IA

Built 2022 Load: 48.3 t ADT: 50

160TH STREET

Good

Over: DD #23

082E10401, Clinton, IA

Built 2016 Load: 48.3 t ADT: 30

160TH AVE

Good

Over: HONEY CREEK

072030504, Des Moines, IA

Built 2011 Load: 48.3 t ADT: 47

IA 2

Good

Over: OVERFLOW

1.6 MI. W. OF I-29, Fremont, IA

Built 2022 Load: 48.3 t ADT: 8,000

CO HOME RD

Good

Over: INDIAN CREEK

084060805, Linn, IA

Built 1993 Load: 48.3 t ADT: 5,794

NB US 65

Good

Over: OVER 4 MI. CK & IAIS RR

2.9 MILES S OF JCT I-80, Polk, IA

Built 1994 Load: 48.3 t ADT: 14,300

NB US 65

Good

Over: DES MOINES RIVER

2.6 MI. S OF JCT. IA 163, Polk, IA

Built 1997 Load: 48.3 t ADT: 12,450

LOCAL

Good

Over: W FORK OF GRAND RIVER

069300513, Ringgold, IA

Built 2009 Load: 48.3 t ADT: 60

LINDEN RD

Good

Over: SNAKE CREEK

081392508, Shelby, IA

Built 2021 Load: 48.3 t ADT: 300

EAGLE BLVD

Good

Over: PEE DEE CREEK

2.1 mi. N of Jct. SR J3T, Davis, IA

Built 1994 Load: 48.4 t

HIGHLAND ACRES RD

Good

Over: LINN CREEK

083180912, Marshall, IA

Built 2007 Load: 48.4 t ADT: 1,630

COUNTY ROAD

Good

Over: BEAVER CREEK

081272304, Dallas, IA

Built 2001 Load: 48.5 t ADT: 51

190 TH

Good

Over: EAST BUTTERICKS CREEK

084292003, Greene, IA

Built 1994 Load: 48.5 t ADT: 30

W RIDGEWAY

Good

Over: SMALL STREAM

CITY CULVERT NO. 49C, Black Hawk, IA

Built 1991 Load: 48.6 t ADT: 4,946

WB US 20

Good

Over: BLACKHAWK CREEK

0.7 MI. W OF JCT. US 63, Black Hawk, IA

Built 1984 Load: 48.6 t ADT: 12,400

620TH ST

Good

Over: TURKEY CREEK

076363302, Cass, IA

Built 2012 Load: 48.6 t ADT: 72

I 80 WB

Good

Over: CEDAR RIVER

1.0 mi. W of W jct. IA 38, Cedar, IA

Built 2010 Load: 48.6 t ADT: 18,250

LOCAL

Good

Over: KNOTTY CREEK

071033603, Des Moines, IA

Built 2006 Load: 48.6 t ADT: 104

B35 180TH ST

Good

Over: SHELL ROCK RIVER

096183301, Floyd, IA

Built 2022 Load: 48.6 t ADT: 49

F24

Good

Over: CLEAR CREEK

080210201, Jasper, IA

Built 2022 Load: 48.6 t ADT: 300

D54 355TH ST

Good

Over: STREAM

086360703, Sac, IA

Built 2022 Load: 48.6 t ADT: 559

US 6

Good

Over: WALNUT CREEK

0.1 mi. E of SR M-47, Pottawattamie, IA

Built 1985 Load: 48.8 t ADT: 1,070

230TH ST

Good

Over: WALNUT CREEK

81130202, Poweshiek, IA

Built 2009 Load: 48.8 t ADT: 20

SIMON RD

Good

Over: WHITEWATER CREEK

087012502, Dubuque, IA

Built 2021 Load: 48.9 t ADT: 275

S 104TH AVE W

Good

Over: CALHOUN CREEK

078202001, Jasper, IA

Built 2015 Load: 48.9 t ADT: 10

FM

Good

Over: DES MOINES RIVER

076183309, Marion, IA

Built 2002 Load: 48.9 t ADT: 3,270

BEECHNUT ROAD

Good

Over: MUD CREEK

074412401, Pottawattamie, IA

Built 2023 Load: 48.9 t ADT: 26

WESTGATE ROAD

Good

Over: HONEY CREEK

077430703, Pottawattamie, IA

Built 2022 Load: 48.9 t ADT: 15

R 63 (180TH ST)

Good

Over: SKUNK RIVER

084 24 12 07, Story, IA

Built 2011 Load: 48.9 t ADT: 219

260TH AVE

Good

Over: SMALL STREAM

000000000, Clinton, IA

Built 2009 Load: 49.0 t ADT: 490

US 218

Good

Over: STREAM

0.5 mi. N of S.R. A23, Mitchell, IA

Built 1986 Load: 49.0 t ADT: 2,530

IA 2

Good

Over: WALNUT CREEK

0.9 MI. W OF W JCT US 169, Ringgold, IA

Built 1988 Load: 49.0 t ADT: 1,750

LOCAL

Good

Over: STREAM

084091901, Benton, IA

Built 2004 Load: 49.2 t ADT: 20

S56 THRUSH AVE

Good

Over: COLD WATER CREEK

1.3 MI S B60, Cerro Gordo, IA

Built 2016 Load: 49.2 t ADT: 344

300TH COURT

Good

Over: WHARAM CREEK

0.5 MI W US65, Cerro Gordo, IA

Built 2018 Load: 49.2 t ADT: 350

B54 240TH

Good

Over: E FORK WAPSIPINICON

095123101, Chickasaw, IA

Built 2018 Load: 49.2 t ADT: 511

D35 215TH ST

Good

Over: BLACKHAWK CREEK BRANCH

088153403, Grundy, IA

Built 2021 Load: 49.2 t ADT: 903

S 96TH AVE W

Good

Over: WALNUT CREEK

078211603, Jasper, IA

Built 2004 Load: 49.2 t ADT: 80

27TH ST SW

Good

Over: DRAINAGE

between 28th and 29th Ave, Linn, IA

Built 2016 Load: 49.2 t ADT: 1,310

100TH ST

Good

Over: OCHEYEDAN RIVER

100th St ov Ocheyedan Riv, Osceola, IA

Built 2019 Load: 49.2 t ADT: 60

LOCAL

Good

Over: MUD CREEK

078220404, Polk, IA

Built 1990 Load: 49.2 t ADT: 71

FM

Good

Over: CAMP CREEK

078221103, Polk, IA

Built 1985 Load: 49.2 t ADT: 110

FM

Good

Over: BIG CREEK

081250901, Polk, IA

Built 1990 Load: 49.2 t ADT: 150

LINDEN RD

Good

Over: SMALL STREAM

079383002, Shelby, IA

Built 2018 Load: 49.2 t ADT: 390

K 30 EAGLE AVE

Good

Over: SMALL STREAM

094462902, Sioux, IA

Built 2019 Load: 49.2 t ADT: 638

Showing 15,651-15,700 of 20,753 bridges

Related

All states → | National rankings → | Understanding conditions → | SD bridges explained →
Data sourced from the FHWA National Bridge Inventory (NBI), latest released cycle. See our methodology for details. Retrieved and formatted by PlainBridges Editorial.

Disclaimer: This information is provided for informational purposes only and does not constitute professional advice. Data is sourced from the FHWA National Bridge Inventory (NBI). A "structurally deficient" rating is a repair-priority signal, not a closure or unsafe-to-cross designation. Consult a qualified civil engineer before making decisions based on this data.

Understanding Bridge Conditions

How FHWA rates bridge condition on a 0-9 scale.

Check Your Daily Bridges

How to look up bridge condition data for bridges on your route.

Read our methodology — how this data is sourced, computed, and verified.